Detachable electrical connectors



Nov. 5, 1968 w. J. LESSNER DETACHABLE ELECTRICAL CONNECTORS Filed July 25, 1966 FBG INVENTOR. WILLIAM J. LESSNER BYM 4 7? l 2; m

ATTORNEYS United States Patent 3,409,867 DETACHABLE ELECTRICAL CONNECTORS William J. Lessner, Cleveland, Ohio, assignor to EFC Incorporated, Cleveland, Ohio, a corporation of Ohio Filed July 25, 1966, Ser. No. 567,689 3 Claims. (Cl. 339-258) ABSTRACT OF THE DISCLOSURE A quick-disconnect electrical connector for receiving and releasably retaining a male tab connector. The quickdisconnect connector includes a floor portion and overlying ear portions. A portion of the floor is struck out to provide a tongue which extends upwardly from the floor and then downwardly toward the floor. The tongue has an end portion which is initially spaced from a detent member on the fioor so that when a male tab member is inserted within the connector, the tongue portion will be flexed downwardly until the downwardly turned end portion of the tongue engages and is stopped by the detent.

This invention relates to detachable electrical connectors of the type having mating elements which are joined together to form a separable connection between two or more conductors, and more specifically to a locking means between detachable connectors of this type.

As is known to those familiar with the art, detachable connectors are of two general classes, one class including those connectors having mating elements which are mechanically locked together when assembled and which cannot be separated thereafter except through the use of special tools or by manipulating the mating elements or other locking structures to mechanically unlock the same. Detachable connectors of the second class include those connectors generally known as quick-disconnect connectors, such as terminal clip type connectors, where the mating elements are separable under predetermined ten- The detachable connector elements comprise male and female plug and socket members and at least one of these elements is provided with an open ferrule portion which is crimped onto an electrical conductor. Usually, at least the female connector is provided with such a ferrule portion. Detachable electrical connectors are usually stamped from copper or brass which is alloyed and/or heat treated to exhibit spring characteristics in the female socket portion but which is sufficiently malleable to permit the ferrule portion of the connector to be crimped onto its conductor. Ideally, the ferrule portion of such a connector should be dead soft while the connector portion should possess strong spring characteristics.

According to some prior art practices, therefore, the connector is fabricated from copper or a copper alloy which Will exhibit strong spring characteristics in the unannealed state and the ferrule portion is then annealed to a soft condition. Obviously, such a technique is expensive, since it involves the provision of special annealing machinery and extra manufacturing steps. Most prior art connectors, therefore, have been fabricated from copper or brass having a hardness that is a compromise between a material having the optimum spring characteristics for the connector end portion and the optimum malleable characteristics for the ferrule portion.

The connector according to this invention overcomes this prior art dilemma by providing a quick-disconnect connector having a female connector portion which may be fabricated from a relatively soft material so that it may be easily worked and crimped onto an electrical conductor, and which has a mating portion which is designed 3,409,867 Patented Nov. 5, 1968 to exhibit strong spring characteristics when it is connected to a male portion of another connector.

It is an object of the present invention to provide a quick-disconnect connector which may be fabricated from a relatively soft material to facilitate crimping of the connector onto an electrical conductor and which will exhibit strong spring characteristics in its mating end portion.

It is a further object of this invention to provide an easily fabricated, quick-disconnect connector having a relatively simple design and which may be connected and disconnected many times without a significant decrease in its retention and electrical contact characteristics.

These and other objects, advantages, and features of the invention will become more fully apparent from the following detailed description and from the accompanying drawings.

In the drawings:

FIG. 1 is a perspective view of the female portion of a quick-disconnect connector according to this invention;

FIG. 2 is a cross sectional view of the connector, the plane of the section being indicated by the line 2-2 in FIG. 1;

FIG. 3 is a cross sectional view similar to FIG. 2, but showing a portion of a male connector element being inserted within the female connector;

FIG. 4 is a cross sectional view similar to FIG. 3 but showing the male connector element fully inserted within the female element;

FIG. 5 is a front elevational view of the connector illustrated in FIG. 1; and

FIG. 6 is a fragmentary perspective view of the male connector element illustrated in FIGS. 3 and 4.

Referring now to the drawings, a female socket element 10 of a quick-disconnect connector is illustrated. The socket element 10 is stamped from a strip of relatively soft copper or brass, such as one-half hard copper, by progressive stamping techniques. The socket element 10 comprises a cylindrical ferrule portion 11 and a forward mating portion 12. The ferrule portion 11 is intended to be crimped onto the bared end portion of an electrical conductor (not shown) by conventional crimping techniques. The forward mating portion 12 comprises a relatively flat floor 13 having a pair of spaced ears 14 and 15. The ears 14 and 15 extend upwardly from the floor 13 and then curve downwardly toward the floor and have end portions 17 and 18 respectively which comprise resilient biasing means to urge a male tongue portion toward the floor in a manner which will hereinafter become apparent.

The floor 13 of the forward mating portion 12 has a relatively long leaf spring tongue 19' which is struck out of the floor during the progressive stamping operation. The leaf spring tongue 19 includes a relatively straight portion 20 which extends upwardly from the floor at an angle of about 15 degrees and a downwardly bent portion 21 having an end 22 which is in closely spaced adjacency to an end stop portion 23 of the floor 13.

The portion 23 comprises that portion of the floor 13 from which the end 22 is severed. The cross sectional thickness of the downwardly bent portion 21 of the tongue 19 is thinned during the progressive stamping operation so that it is relatively flexible as compared to the straight portion 20.

As was previously indicated, the female socket portion 10 is intended to mate with a male blade or tab portion 24 of an electrical connector. The tab portion 24 may be attached to a terminal post (not shown) or may have a ferrule portion (not shown) similar to the ferrule portion 11 of the connector 10. The tab portion 24 comprises a flat bladelike insert having a beveled edge 25 and top and bottom indentations 26 and 27 respectively.

As may be seen in FIG. 3, as the tab portion 24 is inserted into the female socket portion 10, the upper surface of the tab portion 24 engages the end portions 17 and 18 of the ears 14 and 15 and the lower surface of the tab 24 engages the tongue 19. Since the tongue 19 comprises a relatively long leaf spring, it is urged downwardly by the tab 24 until the end 22 engages the end stop portion 23 of the floor 13. During the initial movement of the tab 24 into the socket element 10*, the tongue 19 moves downwardly until the end 22 engages the portion 23 of the floor 13. With the end 22 prevented from further downward or longitudinal movement by engagement with the portion 23, the tongue 19 ofiers some re sistance to further insertion of the tab 24, but the downwardly turned, thinned portion 21 of the tongue 19 may flex to permit further insertion of the tab 24 until the juncture between the downwardly turned portion 21 and the portion 20 snaps into the indentation 27 in the tab 24. Flexure of the downwardly turned end portion 21 of the tongue 19 then exerts an upward force on the tab 24 while the ears 14 and 15 exert a downward force on the tab portion 24 to firmly retain the tab portion 24 within the female connector 10.

Thus, the quick-disconnect connector according to the present invention otters an initially small resistance to the insertion of the tab portion 24, since the tongue 19 is easily moved downwardly until the end portion 22 engages the portion 23. The resistance increases only after the end portion 22 engages the portion 23 during the last increments of insertion to firmly retain the tab portion 24 within the socket element 10.

The invention is not restricted to the slavish imitation of each and every one of the details set forth above. Obviously, devices may be provided which change, add, or eliminate certain features without departing from the scope of the invention.

What is claimed is:

1. An electrical connector for engaging and releasably retaining a male tab connector, said electrical connector comprising a floor portion and overlying ear portions, said floor portion having a tongue extending upwardly from a juncture zone between the tongue and said floor portion and then downwardly toward said floor portion, and a detent member on said floor portion in spaced adjacency to the downwardly turned portion of the tongue, said tongue being movable from its upwardly extending position to a position wherein an end of the downwardly turned portion of the tongue abuts said detent member and said end is prevented from further movement both downwardly and longitudinally relative to the floor portion by said detent member so that, when a male tab member is inserted within the electrical connector between said ear portions and said tongue portion, the tongue portion will be moved downwardly until the downwardly turned end portion of the tongue engages and is stopped by said detent.

2. An electrical connector as set forth in claim 1 wherein said tongue initially extends in an upward direction from said floor at an angle of about 15 degrees with respect to said floor.

3. An electrical connector according to claim 2 wherein said downwardly turned end portion is thinner in cross sectional thickness than the remainder of said tongue to permit flexing of said end portion.

References Cited UNITED STATES PATENTS 2,738,485 3/1956 Batcheller 339-256X 2,759,165 8/ 1956 Batcheller 339-256 FOREIGN PATENTS 858,115 1/1961 Great Britain.

MARVIN A. CHAMPION, Primary Examiner.

P. TEITELBAUM, Assistant Examiner. 

